The One-Arm Lunge Press is a fantastic exercise because it hits a little bit of everything: quads, glutes, abs, and arms.
Step 1: To get into position, grab one dumbbell (DB) and hold it in your left arm. Have your elbow bent, even with your shoulder and your forearm going straight up, ready to press the DB up as if doing the military press. Then get into a lunge position, with your right leg forward and your left leg back. It should look like this:
Step 2: As you press through your right heel to come up from the lunge, do an overhead press with the DB in your left hand. Keep your torso straight, chest up and shoulders back.
Step 3: Come back down into the lunge, bringing your left elbow back down, even with your shoulder. You should be in the same position as you started in Step 1.
Repeat this motion 12 times. Then, switch the DB into your right hand, and do the same One-Arm Lunge press 12 times, this time doing the overhead press with your right arm and performing the lunge with your left leg forward and right leg back.